The two portions of the work area on either side of the split bar appear side-by-side. They scroll in unison vertically, but they scroll independently horizontally.

The application is responsible for specifying the position of the split bar, which is defined with the xVertSplitbar field. Also, the rightmost column of the left split window is specified with the pFieldInfoLast field. xVertSplitbar and pFieldInfoLast are fields of the CNRINFO data structure.

The left split window cannot be empty if there is data in the right window. The right split window is not required to have data. However, because data cannot be scrolled from the right split window into the left split window, or from left to right, the split bar loses much of its usefulness if the right split window is empty.

The user can drag the vertical split bar within the limits of the window. As the user drags the split bar to the left, the right split window becomes wider; as the user drags the split bar to the right, the left split window becomes wider.

Each container control can have one vertical split bar. Horizontal split bars are not supported.